The present invention relates to an electrophotographic copier, facsimile transceiver, laser printer or similar image forming apparatus and, more particularly, to a combined cleaner and toner magazine (CTM) made up of a toner supply device for supplying a dry developer, or toner, to a developing unit for developing an electrostatic latent image formed on an image carrier, and a cleaning device for removing and storing the toner which will be left on the photoconductive element after the development.
It is a common practice to replace such a CTM with new one when a waste toner tank included in the cleaning device is filled up with the removed or waste toner and a toner reservoir included in the toner supply device is emptied substantially at the same time. The CTM can be easily replaced by the user and, therefore, facilitates maintenance of the image forming apparatus of the kind mentioned above. For this reason, the CTM is extensively used with modern image forming apparatuses. In the conventional CTM, the cleaning device or section has a cleaning blade held in contact with the photoconductive element for removing the toner remaining thereon, and a raking brush for collecting the removed toner in the waste toner tank. However, the raking brush cannot fully collect the toner in the waste toner tank alone, i.e., causes some toner to remain on the photoconductive element. Hence, when the used CTM is removed from the image forming apparatus, it is likely that the toner left on the photoconductive element is scattered around in the apparatus to effect image formation and image quality. To eliminate this problem, a magnet shutter may be associated with the waste toner tank for catching the remaining toner in the event of replacement of the CTM, as proposed in the past. However, when the magnet shutter is simply implemented as a rubber magnet sheet, it is not satisfactorily resistive to the toner. Moreover, the rubber magnet sheet would catch not only the toner of interest but also a toner floating in the apparatus, failing to fully exhibit the expected function thereof.
The CTM is easy to replace and maintain, as stated earlier. However, discarding all of the used CTMs is not desirable not only from the resources standpoint but also from the environmental pollution standpoint. In addition, the frequent replacement of the CTM, of course, prevents the image forming apparatus from being operated cost effectively.